Micron size polymer particles are conventionally used in inks, filtration systems, nano-applications, nebulizers, spraying systems, powder coatings of metal and/or other objects and other devices and applications, such as separation chemistry and related analytical methods. Based on the wide variety of applications of these particles, it is important to produce them out of materials and compounds that are readily available, easy to produce and/or manufacture, and cost-efficient to the manufacturer.
In conventional particle production, several different types of polymers may be used, such as melamine resins, fluorescently-labeled polymers, carboxylate-modified polymers, latex, polystyrene-based polymers and polyvinyltoluene-based compounds; however, difficulties arise with respect to preparation of some particles, such as requirements for unusual materials and unusual techniques like cryogenic grinding. Polyamide polymers would be an ideal material to use to form micron-sized polymer particles, but difficulties arise especially when using these materials to produce the polymer particles, such as the requirement for unconventional solvents and as mentioned cryogenic grinding.
EP 733474 describes sealable polyolefin laminated films that may contain particulate hollow bodies or vacuoles. These hollow bodies are defined as “essentially closed polymer skin sheathes” having “an inner gas- or air-filled volume”. Furthermore, these hollow bodies are formed in situ after vacuole-initiating particles are placed in contemplated films. The hollow bodies are not formed independently of the film or matrix that they are to be incorporated in to form the product. Formation of the hollow bodies in the film protects the hollow bodies from destruction and/or damage. Also, the hollow bodies are formed in the film to provide an opaque or “mother of pearl” quality to the film.
To this end, it would be useful to prepare and/or produce micron-sized solid polymer particles a) by using conventional and widely available solvents and conventional methods; b) that comprise nylon-type materials, given that nylon is a conventional and readily available material; c) that can be either opaque and transparent polymer particles; d) that can be readily formed independently of the final film or coating that the particles may be utilized in for other applications; and e) that can be reliably produced in a relatively narrow distribution of polymer particle diameters.